After, place the spinach on a sieve. Press the spinach down using a wooden spoon to drain the excess liquid. Once it is dry enough, transfer it to a large mixing bowl. Add the eggs, feta cheese and the pepper. Mix well. Season it with salt and pepper to taste.

Place a pastry sheet on a flat surface and brush it with melted butter. Top it with another layer of filo pastry. Again, brush it with melted butter. Repeat this until you form 10 layers or half of the pack of the filo pastry.

Put the buttered pastry layers at the bottom of the baking dish and then spoon the spinach and cheese mixture over the pastry. Smoothen it using a spatula.

Butter the remaining pastry the way you did earlier, brushing every other pastry. Place the filo pastry layers over the spinach filling. Next, get a sharp knife and then score the top layer of the pastry into 24 squares. Brush it with butter.

Bake the spanakopita for40-50 minutes until it is crisp and golden brown. Remove from oven and let it cool completely. Cover and refrigerate it for 4 hours up to overnight.

Slice the spanakopita into squares before serving. Serve warm or cold. If you want to reheat them, just preheat them in the oven for 10-15 minutes until they are heated through.